Wireless ad hoc networks are networks in which nodes form a network with their neighboring nodes without the need for a fixed infrastructure. Data transmission is commonly performed through flooding, where every node sends and receives a packet and forwards it. This increases the energy consumption of the node, which results in nodes dying faster, thereby reducing the network lifetime.

This paper proposes energy-efficient reliable routing algorithms for mobile ad hoc networks by addressing all three essential requirements: energy efficiency, link reliability, and network lifetime. Two algorithms, reliable minimum energy cost routing (RMECR) and reliable minimum energy routing (RMER), are developed for hop-by-hop (HBH) and end-to-end (E2E) networks. The energy cost of a path is analyzed by “considering the impact of limited retransmissions across each link, the size of data and ACK packets, and the reliability of E2E paths.”

To find a minimum energy cost path, Dijkstra’s shortest path is employed. RMECR assigns link weights by considering “the expected battery cost of nodes along the path to transfer a packet from the source to the destination”; RMER considers the energy consumed by all nodes involved in the packet transmission.

Simulation results show that both RMER and RMECR outperform existing algorithms in obtaining reliable routes since both consider individual components of the transceiver in calculating the node energy instead of just the transmission energy.